Metal-extractor for rotary mills.



M. F. WILLIAMS.

METAL EXTRACTOR FOR ROTARY MILLS.

APPLICATION FILED IAN.16. |917.

1,258,970. Patented Mar. 12, 1918.

.has been subject to becoming quickly 'MILTON F. WILLIAMS, OF ST. LOUIS, MISSOURI, ASSIGNOR TO WILLIAMS PATENT CRUSHEB. AND PULVERIZER COMPANY, OF ST. LOUIS, MISSOURI, A CORPORATION 0F MISSOURI.

METAL-EXTRACTOR FOR ROTARY MILLS.

To all whom t may concern.'

Be it known that 1, MrL'roN F. WILLIAMS, a citizen of the United States, residing at St. Louis, Missouri, have invented a certain new and useful Improvement in Metal- Extractors for Rotary Mills, of which the following is a full, clear, and exact description, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, forming part of this specification.

This invention relates generally to rotary mills of a type designed for the reduction of various materials, and pertains specifically to certain features of construction by virtue of which the reducing apparatus, in the course of its operation, vwill free itself ot any refractory material which may be fed to it inadvertently, and thereby protect the working parts against injury.

As the use of extractors or separators with such mills is shown in the prior art, applicants present invention relates to a particular form thereof which is designed to fulfil certain requirements and uses not satisfied by the prior structures. 1n prior practice, it has been customary to provide some form of a. pocket or receptacle communicating with the grinding chamber in which rotary beaters or hammers operate, the mouth or communicating portion of the receptacle being disposed tangentially with respect to the orbit of the beaters and lying across the zone of centrifugal projection thereot. lin prior devices, inthe absence of inhibiting means which applicant has hitherto employed, this receptacle designed for the reception of the extraneous material, illed and clogged with the material upon which the mill is operating, thus requirin the frequent emptying of the receptac e in order to maintain its eiicacy vior the intended purpose.

It is the specic object of applicants present invention to provide such a 'formi of extractor or separator as will not be subject to the rapid illing up and clogging referred to, and which will be highly efficacious in coperating with the operating parts of the mill to secure the elimination and extraction of extraneous material tro the Specification of Letters ratent. Patented llt/liar. 112, 11918.

Application led January 16, 1917. Serial No. 142,659.

By reference to the accompanying drawings orming a part of this specification, let it be understood that Figure 1 represents a vertical sectional vlew of my improved apparatus, the same being taken longitudinally of the machine;

and

Fig. 2 represents a detail, the same being a section taken on line 2-2 of Fig. 1.

Referring to the device herein illustrated, by means of the characters of reference, let 1 represent a suitable base, foundation, or support for the mill casing 2 which is closed by a suitable cover portion 4 and provides a support for the shat't 5. Shaft 5 carries hammer mounts 6 upon which are mounted the hammers or beaters 7. A cage 8 cooperates with the cover portion t to provide a grinding cylinder in which material is held to the operation of the beaters 7. A throat member 9 forms a conduit having communication with the grinding chamber, whereby material may be fed to the latter from a suitable hopper 10. A breaker plate 11 of any d'esired construction 'forms a portion of the grinding chamber adjacent the inlet from the conduit 9 but beyond the same in the direction of movement of the beaters. Intermediate the feed conduit 9 and the breaker plate 11, a conduit 12 has communication with the grinding chamber. rlhe conduit 12 is presented tangentially with respect to the orbit of the beaters, and lies across the zone of centrifugal projection therefrom. 1t slopes abruptly upward from the grinding chamber at a considerable angle Vfrom the horizontal and supports a' metal catcher 14 of special design. This metal catcher is in the form of a housing or casing inclosed by a top wall 15, a bottom wall 16, side walls 17 and an end wall 18. Its position with respect to the grinding chamber is such that it lies entirely above the latter and above the conduit 12, and has a constant slope toward the latter. Adjacent its lower extremity its upper wall is deected or slightly converged toward its lower wall to a point indicated by the numeral 19, and thence the upper wall dares upwardly and outwardly away from the lower wall. The lower wall, for the most part, is removable from the other walls, being hinged at 20, and is removably held the side and w by suitable catches 21. Supported upon the lower wall 16 are angles or baffles 22 which extend thereacross intermediate the side walls 14, and upwardly partially across the depth of the receptacle toward the upper wall 15. An adjustable gate 24 projects intermediate the conduit 9 and the conduit 12 and is operable to vary the discharge area of the former.

In the operation of the device, material is fed to the grinding chamber from the hopper 10 through the conduit 9 while the shaft 5 is suitably driven to revolve the beaters 11 at a high rate of speed. Upon its entrance into the grinding chamber, the material is caught by the rapidly revolving beaters and impinged against the breaker plate 11 where it is reduced and then carried forward by the beaters across the cage 8 whereon it is further reduced until of size proper to screen through the openings in the cage.

In case refractory bodies, such as pebbles, pieces of metal or the like, are fed into' the grinding chamber with the material, they will be struck by the beaters as the latter pass the feed inlet and will be projected through the conduit 12 and into the metal l catcher 14: wherein they will fall under the influence of gravity and be caught behind the ballles 22, whereby they are retained against rentrance into the grinding chamber. rl`he material upon which the mill is operating, being of lighter or more friable nature than the refractory materials which it is desired to extract, will not be propelled with the same force and momentum as are the refractory bodies, and hence will not be projected into the metal catcher to the ex,- tent to which are the latter. 'Ihe restricted area of the metal catcher at the point 19, due to the convergence of the upper wall and the presence of the baflies, tends to stop the lighter or more friable material and prevent its entrance completely into the metal catcher so that it is returned to the grlnding chamber through the downwardly sloping conduit l2. Furthermore, the operation of the beaters tends to .raise the air pressure in the metal catcher 14 so that the entrance thereinto of li ht material is effectively inhibited. In this fashion the filling up 'of the metal catcher with the material which it is intended to reduce, is prevented to a great extent, so that the eflicacy of the wall 16 from the catches 2l and permitting its swinging open to dump the collected material.

While I have above described the principles of operation of my invention together with the apparatus which I now consider to represent the best embodiment thereof, and which has been put in practice, nevertheless I desire to have it understood that the apparatus shown is only illustrative and that the invention can be carried out by means differing in specific particulars therefrom.

What I claim is: j v

1. In a reducing mill, the combination of a grinding chamber having a feed inlet, rotary beaters arranged for operation within the grinding chamber and across the feed inlet, a conduit having communication with the grinding chamber at the feed inlet and sloping constantly upwardly away from the grinding chamber, and a receptacle for extraneous matter arranged at the upper extremity of said conduit at an elevation above the feed inlet; walls of the conduit rst converging and then diverging intermediate the grinding chamber and the receptacle 2. In a reducing machine, the combination of a grinding chamber provided with a feed inlet, rotary reducing elements arranged for operation within the grinding chamber and across the feed inlet, a conduit for foreign material having unobstructed communication with the grinding chamber at the feed inlet and extending in a constant direction upwardly from the feed inlet substantially in the path of centrifugal projection from the beaters, the said conduit terminating in an externally'closed receptacle supported thereabove, said receptacle being provided with means therein for retaining material from sliding from the bottom thereof into the conduit.

In testimony whereof I hereunto a my signature in the presence of two Witnesses, this10th day of January, 1917.

'rou r. ritrarre.

Witnesses:

ELLIOTT S. HANsoN, l H. M. Para. 

